Speed and pressure responsive regulator



Sept- 4, 1934- c. s. BAKER El AL 1,972,517

SPEED AND PRESSURE RESPONSIVE REGULATOR Filed Aug. 5, 1952 I VENTORS. Gfiavies fialcen M agaizmfl'nyam BY 5 f x THEIR A TTORNEY.

l atented Sept. 4,

PATENT; OFFICE SPEED AND PRESSURE RESPONSIVE .:REGULATOR Charles S. Baker, Coming, and Ralph M. Fingar, Painted Post, N. Y., assignors to Ingersoll-Ranfl Company, Jersey City, New Jersey N; J,, a corporation of pp i a on August 5,1932, Serial No. 627,596 7 5 Claims. (0112645 7) This invention relates to governing devices and more particularly to a form of governing device combining pressure control regulation and speed control regulation in such a manner that either' 5 thespeed regulator or the pressure regulator may perform its functions independently of the other.

Devices of this kind are commonly used on internal combustion engines which are used to fur nish power for the operation of a compressor. The necessity for the dual type of control is obvious; Governors of this kind are commonly applied directly to the throttle valve and this valve is so constructed that it is normally urged to its open position either by the action. of gravity or by means of a spring or equivalent device. Thus the throttle valve itself constitutes a load of considerable importance. 7

The usual devices of this kind sufier from the defect of having a relatively wide range due pri-- marily to the factlthat the fixed weight of the valve is in practice transferable fromone control to the other. Thus through the lower'pressure ranges the control of the-engine rests entirely upon the speed governor, but as the pressure increases the pressure governor comes in play and as it begins to operate it transfers the load of the valve from the speed governor to itself thereby suffering a slackening of effect. Thus although the. pressuremay be considerably below the shut-off point and there is no reason for reducing the speed of the engine, the speed governor is out out of operation and the entire governing'function assumed by the pressure governor so that while pressure is buildingup to the shut 35 off point, the engine is run at a constantlydiminishing speed. The effect of this action isto provide a widera'nge for'the governor both with respect .to time and pressure. 1

It is an object of this invention toso' construct the speed governor and the pressure governor that'the fixed loadof the throttle valve shall at all times be effective upon both governors, which operate. separately without transferring any part of "the load from one governor to the other. A further object of this construction is to'reduce the range. of such a combination of governors to a point where the inefficient operation of the en-' gine is reduced to a minimum. Other objects are either apparent or will be referred to'hereinafter. In the accompanying drawing which'is a-representation of'the invention partly-in section A refers generally to the 'throttle device; 3 indicates the pressure control regulator and C rep resents the speed governor;- Boththespeedtcone trol C and the pressure control B are connected,

as will be'h'ereinafter described, to the throttle mechanism A.

Although a carburetor for any type of fuel may be controlled bythis invention it is commonly used with gas operated engines and for that reason a gas carburetor or mixing chamber is herein disclosed-and described. .A mixing valve casing 2 is provided with an air inlet 3 near the upper end thereof. :Air coming through the inlet 3 passes into a chamber 5 whence through ports 7 in an inner wall 6 of the chamber it passes into. an interior ,or mixing chamber 9 through ports 10 in the air throttle valve 8.

Near the bottom of the casing 2 is a gas inlet 11 through which gas is conducted to a gas cham ber"13 whence it is. admitted through ports 15' in the inner wall 6 of the mixing chamber to the mixing chamber 9 through-slots 16 in the gas throttle valve 17. Vents 2-1 are shown in the base of the gas throttle valve 17 to-permit unhampered 75- movement of this valve. The air throttle valve 8 and the gasthrottle valve 1-? are suitably attached to acommon stem 19. 'An outlet 23 from the mixing chamber 9 is provided whereby the gas and air mixture maybe conveyed to the internal combustion engine. I

Surmounting the casing 2 is a cap 22 through which an extension of the shaft 19 passes. A heavy guide member 24 is attached to the shaft 12. .The member 24 is made heavy so that its 85' weight may constantly tend to open the throttle Valve which is itself of heavy construction and is so placed that the force of gravity will tend to hold it open. 'These parts are necessarily of considerable weight as they must fit reasonably close in the inner wall of the mixing chamber and must move readily therein although by reasonof the nature of the fuel used the parts are often likely to be sticky or gummy. Itis important, therefore, that these parts be either 2} artificially weighted or be made of suflicient weight to overcome any friction which may develop .in the mixing chamber. I

The upper end of the cap 22 is provided with guidemeans 25 through which theguide memher 2*; is slidable. The cap 22 also serves as the base for a maximum throttleopening stop member 26 which is simply a screw positioned to intercept downward travel of a pressure regulator arm 30 and a minimum throttle opening stop member 2? which is a similar screw positioned to intercept upward movement of the pressure control known type. An oil reservoir is connected to the interior of the sylphon 33 by a connection 36 in which is placed a needle valve 37. The upper end of the oil reservoir 35 is connected by a pipe 38 to a fluid pressure source (not shown).

Pivotally connected to a lug 39 of the shelf 29 is the pressure control arm 30 upon which is slidably mounted a weight 32 having a set screw 32 to lock it at any desired position. On the.

arm 30 between the pivot connection 40 and the" weight 32 is a notch 41 into which fitsa sylphon knife edge 42. The arm 30 is provided with a bore 43 through which the guide member 24 passes. The guide member 24 itself is provided with a bore 28 into which the end of a bell crank 44 projects. The end of the bell crank 44 is rounded and is adapted to bear against the upper wall of the bore 28 in such a manner as to sup-- port the weight of the guide member 24 and the appended throttle valve assembly. The angle of the bell crank 44 is pivotally mounted in a lug 45 of the control arm 30 so that the weight of the valve assembly is sup-ported through the bell crank 44 by the pressure control regulator B.

The other end of the bell crank 44 is pivotally connected with a rod 46 through a clevis 47. A similar clevis 48 at the opposite end of the. rod 46 is pivoted to an arm 49 of a rocker memberSO which is pivotally mounted upon a lug 51 of a centrifugal governor casing 52 which encloses a governor 53 of a well known type in which a pair of fly balls 54 driven by a shaft 55 and opposed by a spring 56 are adapted to lift a spring casing 5'7 and thereby raise a plunger 58 which bears against the operating end 59 of the rocker member 50. A spring 60 controlled by adjusting means 61- bears against the opposite end 62 of the rocker member 50, and provides an adjustment for the speed control governor.

When the engine is running the drive shaft 55 is rotated and the fly balls 54 are moved out ward by centrifugal force. Their outward movement is converted to vertical movement of the casing 5'7 through the arms 63. This vertical movement is opposed by the adjusting spring 60, the spring 56, and the weight of the valve 'parts until the engine has reached a speed at'which the centrifugal force of the fly balls is capable of overcoming the resistance whereupon the'casing 57 rises carrying with it the plunger 58 which rocks the rocker member 50. Through the connecting linkage including the arm 49 and the rod 46 the bell crank 44 is moved upon its fulcrum and the throttle valve is lifted by means of the guide member 24 and the connecting rod 19.

As the throttle valve rises it cuts off cornmunication between the ports 7 and 10 at the air connection and between ports 15 and slots 16 at the fuel connection, thereby reducing the amount of fuel supplied to the engine, thus cutting down its speed and consequently decreasing the rotative speed of the fly balls so that continued upward movement of the casing 57 is prohibited. The effect of the speed governor is to limit the top speed of the engine, and to maintain a relatively constant speed so long as the pressure fluid stored by thecompressor' run by the engine does not exceed a predetermined pressure, the attainment of which will bring the pressure governor inte action. V

r The lever arm 30 of the pressure control regulator is held upon the maximum speed stop. 26 by its own weight, the weight of the valve assembly, the weigh't of the bell crank and the pressure of the spring 60; These items comprise the hired load of the pressure governor, and the ball 32 is an additional adjustable load. The weight 32 is adjusted upon the arm 30 to balance a predetermined pressure in the sylphon 33. When the pressure in the sylphon reaches the predetermined point the total resistance is overcome and the bellows of the sylphon extends forcing upward the knife edge 42 and lifting the rod 30 off the maximum'speed stop.

' As the rod 30 moves upward carrying with it the lug 45 and the attached bell crank 44 the guide member 24 and its appended throttle mechanism is lifted thereby cutting off the supply of fuel to the engine. The pressure of the spring 60 holds the bell crank in position relative to the arm 30. Movement of the arm 30 slightly affects the angular relationship between the links 49 and46, but does not affect the speed governor except indirectly through operation of the throttle. The upward movement of the arm 30 is limited by the minimum speed stop 27- which prevents an absolute shut down of the engine.

Due to friction, sylphon lag, springs, clearances and the like an unavoidable range limits the instantaneous action of the pressure governor. In practice this may be reduced to a rather low minimum of approximately three pounds. In other words an increase of three pounds pressure will insure travel of the pressure control arm 30 from the maximum throttle opening stop 26 to the minimum throttle opening stop 27. Between what limiting pressures this control shall function depends upon; the setting of the weight 32 upon the lever 30 I, r p 1 Assuming that the range within which the pressure governor works is between 147 and 150 pounds it is conceivable that the load on the engine will be such at the higher pressures that the ,speed of the engine will be reduced below the limit for which the speed governor is set so that the engine will be running at full throttle opening. When at 147 pounds the pressure con} trol arm 30 begins to move upward there will be no effect whatever upon the speed control governor and as the pressure increases from 147 to 150 pounds the arm 30 will pass through the arc between the maximum speed stop 26 and the minimum speed stop 2'7. In such a case the pressure control governor acts inthe same manner as if there were no speed control governor.

If, however, the control is set to operate within lower limits of pressure such as for instance 9'7 pounds and 100 pounds it is probable that the speed control governor will be in an intermediate position and that the throttle may be half closed. When the pressure of 9'7 pounds is reached the pressure governor starts to rise and if the speed governor did' not change, the range of the pressure governor would be reduced to 1% pounds as it would only have to close the throttle halfway (it being already half closed). What happens is that when the pressure governor starts to act to slow down the enginelthe speed governor opposes it sothat each increment that the pressure governor lifts the throttle isneutralized by a corresponding drop of the throttle" by the speed governor until the speed, overnor has returned :to its full throttle position where it is definitely fixed and can not act further; The pressure governor, however, continues to act and then begins to slow down the engine and is workingexactly. the same as in the case of the first a'ssumedposition where the speed governor did not act at all.

it will be seen by the foregoing that the pressure control under all circumstances has a constant range and at some point in that range the speed control will be inefiective, although at no time will it permit overspeeding.

Having thus shown how the objects of the invention are attained, we claim:

1. A governor comprising in combination a throttle valve having a load tending to hold it in open position, pressure responsive control means to actuate it toward its closed position, speed actuated control means to actuate it toward its closed position, support means actuated by the pressure responsive means, and a bell crank pivotally connected to the support means and to the speed responsive means and supporting the entire weight of the throttle valve whereby motion of each control means is communicated to the valve independently of the other control means.

2. A governor comprising in combination a throttle valve having a tendency to assume its open position, a bell crank engaging the throttle to support the entire weight of the throttle valve and adapted to move it to its closed position, and speed responsive means and pressure responsive means each pivotally connected to the bell crank and adapted independently of each other to communicate movement thereto.

3. A governor comprising in combination'a throttle valve having a tendency to assume its open position, a pressure responsive device, means actuated by the pressure responsive device having a bell crank pivoted thereon to support the entire weight of the throttle valve, a speed responsive device connected to the bell crank, and means constantly maintaining the load of the throttle upon the bell crank thereby enabling independent movement of the speed responsive device and the pressure responsive device to be communicated to the bell crank without transference of the load of the valve from one device to the other.

4. A governor comprising a throttle valve having a tendency to assume its open position, a bell crank engaging the valve and being at all times subject to the entire Weight of the valve, a lever on which the bell crank is fulcrumed, speed responsive means operating at changes of speed to rock the bell crank upon its fulcrum thereby actuating the valve, and pressure responsive means operating at changes of pressure to move the lever and the bell crank thereby actuating the valve.

5. A governor comprising a throttle valve having a tendency to assume its open position, a weighted lever, a bell crank supporting the load of the throttle valve and pivoted on the lever, a speed responsive device connected to the bell crank and operating to control its movement relative to the lever, and a pressure responsive device operating within a predetermined pressure range to move the weighted lever, thereby actuating the valve through the bell crank.

CHARLES S. BAKER. RALPH M. FINGAR. 

